Additional Information on Operating Leases (Details)	3 Months Ended
	Mar. 31, 2019 USD ($)
Operating Lease Cost
Operating leases	$ 601,000
Short-term lease	31,000
Total lease expense	632,000
Cash payments included in operating cash flows	$ 585,000
Weighted average discount rate	9.21%
Weighted average remaining lease term in years	5 years 9 months 29 days